 |
|
The Ectasian is the second geological period in the Mesoproterozoic. It began 1.4 billion years ago and ended at 1.2 billion years ago. The Ectasian came after the Calymmian and before the Stenian.
This period shows for the first evidence of sexual reproduction. The 1.2 billion-year-old Hunting Formation on Somerset Island, Canada, is from the end of the Ectasian. It has the microfossils of the multicellular filaments of Bangiomorpha pubescens (a type of red algae). This was the first organism that had sexual reproduction.
| Precambrian (4.567 gya – 541 mya) | |
|---|---|
| In the left column are Eons, bold are Eras, not bold are Periods. gya = billion years ago, mya = million years ago | |
| Hadean (4.567 gya – 4 gya) | Chaotian Zirconian |
| Archaean (4 gya – 2.5 gya) | Eoarchaean (4 gya – 3.6 gya)
Palaeoarchaean (3.6 gya – 3.2 gya) |
| Proterozoic (2.5 gya – 541 mya) | Palaeoproterozoic (2.5 gya – 1.6 gya) Siderian (2.5 gya – 2.3 gya) Rhyacian (2.3 gya – 2.05 gya) Orosirian (2.05 gya – 1.8 gya) Statherian (1.8 gya – 1.6 gya)
Mesoproterozoic (1.6 gya – 1 gya) Calymmian (1.6 gya – 1.4 gya) Ectasian (1.4 gya – 1.2 gya) Stenian (1.2 gya – 1 gya) Neoproterozoic (1 gya - 541 mya) Tonian (1 gya – 720 mya) Cryogenian (720 mya – 635 mya) Ediacaran (635 mya – 541 mya) |
